1. Field of the Invention
The present invention generally relates to a detection device and a method thereof, and more particularly, to an audio-video synchronization detection device and a method thereof.
2. Description of Related Art
An audio-video processing unit is usually built in a multimedia audio-video device, such as a display or a blue-ray player, for converting an image data stream and an audio data stream into an image signal and an audio signal. In addition, before a multimedia audio-video device is shipped, the synchronization state between the image signal and the audio signal output by the audio-video processing unit is detected through an audio-video synchronization detection device regardless of the type of the multimedia audio-video device, so as to ensure that synchronous audio and video can be received by a consumer.
A conventional audio-video synchronization detection device directly measures the difference between the image signal and the audio signal output by the audio-video processing unit and determines the synchronization state between the image signal and the audio signal accordingly. However, in a real application, the image signal and audio signal in the multimedia audio-video device are respectively played by a display panel and a speaker in the application system. Thus, the audio and video received by the consumer respectively come from the display panel and the speaker rather than the audio-video processing unit. Additionally, it may result in signal delays in the process of transmitting the image signal and the audio signal from the audio-video processing unit to the display panel and the speaker and in processing the signals by the display panel and the speaker. As a result, asynchronous audio and video may be received by the consumer.
In other words, the conventional audio-video synchronization detection device ignores the delay errors produced during the transmission of the image signal and the audio signal, which causes the detection result to be different from the actual experience of a consumer. Namely, the conventional audio-video synchronization detection device cannot properly detect the audio-video synchronization quality of the multimedia audio-video device.